During the past three decades, great advances have been made in the computer and data processing fields. The advent and development of electronic microchips has brought computers into the home. In fact, home computers that today can fit on desk top are more powerful and are capable of storing more data than the computers built twenty to thirty year ago that would fill entire rooms.
Today, easily transportable lap-top computers such as the Tandy Model 100 and the Tandy Model 200 are readily available and widely sold. The primary advantage of such lap-top computers is that they can be easily moved and used in various locations at various times. Manufacturers of such lap-top computers, to keep them lightweight and easily portable, have generally combined one or more components into a single housing. One such computer that has enjoyed commercial success weighs only about four pounds and combines the computer, a keyboard, a liquid crystal display and a modem within a single housing. The computers are built so that they can be operated anywhere on battery power. They are small enough and lightweight enough to easily fit into a briefcase or book bag.
Such lap-top computers, however, must generally be connected to other peripheral equipment for them to become a truly effective tool for most applications. It is often necessary for them to be connected to a disc drive for archiving data, and to a printer for making paper copies of work generated at a remote location. There may also be the need to connect the computer to a modem to transmit data to a computer at another location. Further, it may be desirable to connect the lap-top computer to a more sophisticated display, memory and input devices.
Many users find it is necessary to make as many as a dozen separate electrical connections to connect the necessary peripheral equipment to their lap-top computer. The cable connectors traditionally used to interconnect the components were not designed for frequent connection and disconnection and tend to wear out quickly. Also, the process is somewhat time consuming.
Other disadvantages arise from the need to make numerous electrical connections on a relatively frequent basis. Cable connections, for example, unnecessarily reduce system reliability. The need for numerous cables and several separate power supplies causes the cost of the system to be unnecessarily high. Such systems also require more physical space to set up and operate than is desirable. More electrical energy is unnecessarily consumed because each of the components has its own power supply. Further, if the connections are made improperly, damage can be done to the hardware and software. Data stored in the memory could also be lost.
Most users, therefore, would find it desirable to have either a portable computer with greater capacities so that the peripheral equipment would not be necessary. Alternatively, such users would find it desirable to have an apparatus such as that of the present invention which would expand the capabilities of lap-top computers, greatly speed up the process of connecting computer components, eliminate the possibility of improper cable connection, require no special skill to operate, reduce maintenance costs, improve service life and reliability, reduce electrical energy consumption, reduce the physical space requirements, and reduce the connection time from a considerable number of minutes to just a few seconds.
In the prior art there have been several approaches to expanding the capability of data processing equipment. However, none of these efforts have achieved all of the advantages of the present invention. For example, U. S. Pat. No. 3,940,758 to Margolin dated Feb. 24, 1976 is directed to an expandable keyboard for a pocket-type calculator which is made in modular form with the various modules hinged together. Normally the modules form a stack. The modules, because they are hinged, can be folded out to form a much larger keyboard with more keys than the keyboards found on conventional pocket calculators. While somehwat pertinent because it generally relates to problems similar to those solved by the present invention, the approach is clearly different. It is not directed to a means for attaching peripheral components. Instead it is directed to a manner in which a set of components can be configured to reduce their overall size.
Also of interest is U.S. Pat. No. 4,564,751 to Alley et al dated Jan. 14, 1986. This patent is not directed toward an apparatus which permits multiple peripheral components to be attached to a lap-top computer. Instead, it is directed to a wrap-around auxiliary keyboard which is used to input data. The basic purpose of this design is to prevent keyboard incompatibility so that software compatible with a first hardware computer system such as an IBM PC may be run on a second otherwise incompatible computer hardware system such as an Apple MacIntosh. This is an entirely different problem than that solved by the present invention.